3D Driving Game 4.0 offers a realistic open-world driving experience set in the city of Seoul, Korea. Players can immerse themselves in various missions like bus and taxi driving, while also enjoying the freedom to purchase and customize a wide range of vehicles using the 3D custom object editor. The game features a unique "Custom Texture" option, allowing players to personalize their cars with custom exterior paint or imported images. Explore hidden secrets across the map, including mountain drives, schools, and historical sites within Seoul.

In addition to the single-player mission mode, players can engage in multiplayer gameplay with friends, adding a social element to the driving experience. The game's realistic traffic system brings the city to life with a variety of AI-controlled vehicles, providing a dynamic environment for players to interact with as they explore the virtual Seoul.